Number of labeled rooted trees with a degree constraint: ((3*n)!/(6^n)) * binomial(3*n + 1, n).

A036771

Number of labeled rooted trees with a degree constraint: ((3*n)!/(6^n)) * binomial(3*n + 1, n).

Terms

    a(0) =1a(1) =4a(2) =420a(3) =201600a(4) =264264000a(5) =734557824000

External references